The present invention relates to a method and apparatus for printing electronic document data containing a large amount of image data such as graphic images on a sheet of paper, and restoring the original electronic document data based on the data printed on the sheet of paper.
There has been conventionally known an apparatus for reading data printed on a paper sheet through a scanner and creating electronic document data including characters and images, for example, in order to reuse the contents of the documents printed on the distributed sheet of paper.
Jpn. Pat. Appln. KOKAI Publication No. 10-224540 discloses a digital copier which creates electronic document data by recognizing code patterns which are easy to read for computers such as griff code (Xerox USA) and bar codes and printed on paper.
Such conventional systems however take a long time to recognize characters and still cannot recognize 100% of the letters. As a result, inaccurate electronic document data are created.
Moreover, if the print data to be converted to electronic data contain e.g. color images and thus the amounts of data are large, it may be difficult to print all the code patterns corresponding to the entire print data on e.g. the back of the sheet. In such a case, it is impossible to create electronic document data.
Thus, in a conventional arrangement, it is difficult to restore electronic document data if the print data containing e.g. color images and thus all the code patterns corresponding to the entire print data cannot be printed.